Submarine cable



Dec. 1,1931. 5 FlSCHER 1,834,124

SUBMARINE CABLE Fild Oct. 11, 1929 Patented Dec. 1, 1931 UNITED STATES PATENT OFFICE ERNST FISCHER, OI BERLIN-TEMPELHOI', GERMANY, ASSIGNOR TO SIEMENS- .A CORPORATION 01 GERMANY SUBHARINE CABLE Application filed. October 11, 1929, Serial No. 388,860, and in. Germany October 6, 1928.

My invention relates to improvements in submarine cables, and more particularly to submarine cables loaded with Pupin coils. I

In submarine cables loaded with Pupin coils it is very (lifiicult to construct the coil elements in such manner that they are able to withstand the pressure of the water at great depths. It has already been suggested to place the coil elements in a pressure resisting tube which is filled with a. filling compound or'other non-compressible substance. It has, however, been ascertained that this construction has the drawback that the pressure of the water acting on the tube is transmitted to the 15 coils, articularly the pressure acting axially from th ends, and is liable to damage them. It has also been proposed to construct the coils located in the interior of a waterproof shell in such a manner that the interior of the shell filled with non-compressible substances contains spaces or chambers filled with easily compressible substances. This has, for instance, been attained by fillin the boxes containing the coils wih an easi y compressible substance while the remaining portion of the watertight shell is filled with a non-compressible substance.

ccording to my invention a still better protection is obtained for the coils by filling not only the boxes or other receptacles containing the individual coils but also the space outside the boxes in the interior of the waterproof shell with an easily compressible substance. In this way the result is obtained that thewater pressure is unable to act on the coil windings and the coil cores at all or at least not with a detrimental strength.

The drawing affixed to my specification illustrates an embodiment of my invention by way of example.

In this drawing showing a longitudinal section 1, 2, 3 and 4 are the airtight pressureproof steel boxes, each containing a Pupin coil 11, 21, 81, 41 respectively. Each box encloses its coil with a certain clearance. This space is filled wth an easily compressible substance, such as air or another gas or with a spongy substance (sponge rubber). The boxes are located in a row in the interior of a 50 preferably pressure-proof flexible tube 5.

0]? BERLIN SIEMENSSTAD'I', GERMANY,

This flexible tube tapers in known manner towards its ends. It consists, for instance, of a. wire helix with superimposed lead sheath. The space 6 within the sheath outside the boxes containing the coils is accordin to my invention filled, the same as the col? boxes, with an easily compressible substance (air, gas, spongy rubber).

I claim as my invention:

1. Pupin c'oil loading section for submarine cables comprising a waterproof pressure re sisting sheath, loading coils and individual casings for said loading coils, and compressible substances filling all remaining empty spaces between said casings and said waterproof sheath and between the wall of each casing and the loading coil contained therein..

2. Pupin coil loading section for submarine cables comprising a' waterproof pressure resisting sheath, loading coils and individual casings for said loading coils, and a sponge rubber filling for all spaces between said casings and said waterproof sheath and between the wall of each casing and the loading ooil contained therein.

In testimony whereof I afiix my signature.

\ ERNST FISCHER. 

